20)7 



The generic name Maurina was first used by Muller for a group 

 of 3 species found by him in southern Brazil in situations similar to 

 those in which calif or niensis occurs — rather swift running water*. 

 The larvae agree with the larva of calif ornicnsis and differ from 

 others belonging to Pericoma in having a medio-ventral scries of 

 sucker-like discs, one on each abdominal segment except the last, and 

 the pupae, with their oval shape and flat appearance, conform to the 

 same grouping. Eaton has subdivided the genus Pcricouia into sev- 

 eral genera, but upon adult characters only. 



I have not seen any stage of calif ornicnsis, no suitable situations 

 for its occurrence being in this part of the state. 



The wing venation of the imago as figured by Kincaid differs 

 from that of the normal Pericoma, and in the absence of the base of 

 tlie anterior branch of the posterior furcate vein resembles that given 

 by Muller for the Brazilian species. 



PsYCHODA Meigen 

 Keys to Species 



LARVAE 



1. Thorax without well-definod ehitinized transverse plates 2 



— Thorax with well-defined ehitinized plates 6 



2. Abdomen without ehitinized dorsal plates minuta. 



— At least sixth and seventh segments with ehitinized dorsal plates. .3 



3. Sixth and seventh abdominal segments eaeh with 3 ehitinized trans- 



verse dorsal plates 4 



— Fifth, sixth, and seventh abdominal segments Avith ehitinized trans- 



verse dorsal plates 5 



4. Thoraeie and abdominal segments, except sixth and seventh, eaeh 



with a closely approximated pair of hairs on a small circular plate 

 near the posterior lateral margin nocturnala. 



— Thoracic and abdominal segments without such hairsf . . . .ftchizura. 



5. Fifth, sixth, and seventh abdominal segments eaeh with 3 ehitinized 



transverse dorsal plates alhimacidata. 



— Fifth and sixth abdominal segments eaeh with 3 ehitinized trans- 



verse dorsal plates, seventh with 2 floridica. 



6. Prothoraeic segment with one ehitinized plate, metathoracie seg- 



ment with 2 such plates ; abdominal segments, except 6 and 7, 



without ehitinized plates alternnta. 



■ — Eaeh thoracic and abdominal segment with a ehitinized plate on 

 eaeh annulus 7 



*Trans. Ent. Soc. London, 1895, p. 480. 



tNeither mentioned in description nor drawn in fignres by Fullaway, so assumed 

 to be absent. 



